Nearly seven months after they voted in an election on 15 March, Dutch voters are to get a new government after the leaders of four parties agreed on a centre-right policy programme.

The prime minister, Mark Rutte, is expected to present a rocky four-party coalition to his MPs on Monday, 208 days after his liberal VVD party won the March polls.

The negotiations have been the longest to form a new government in modern Dutch history and will be officially presented to parliament on Tuesday, when the process of appointing ministers will begin.

“I am very happy,” said Rutte, who will form his third ruling coalition. “Precisely on the day that this [government] formation is overtaking the longest previous formation we have ... a negotiators’ agreement.”

Cementing a stable marriage between Rutte’s business-friendly VVD, the progressive D66 and two Christian parties, the relatively moderate CDA and the far more conservative Christian Union, may however prove challenging.

D66 is pro-choice, pro-LGBT rights and pro-EU, and wants pioneering Dutch euthanasia laws extended so that not just terminally ill patients can decide to end their lives. The Christian Union is opposed to abortion, same-sex marriage and euthanasia, and has in the past argued that the Netherlands should pull out of the eurozone in its present form.

Nonetheless, agreement on the government’s key policies – on tax, sick pay, welfare payments for refugees, and defence and education spending – has reportedly been reached.

The D66 leader, Alexander Pechtold, said that after years of austerity, the new government will reward voters with lower taxes. “We are coming out of crisis, so we can invest, taxes can be lowered,” he told reporters.

The new coalition will have a majority of just one in the fragmented 13-party, 150-seat Dutch parliament and its ability to survive a four-year term is likely to prove the toughest test yet of Rutte’s consensus-building skills.

The prime minister has previously governed with the support of the far-right, anti-Islam Geert Wilders and in a coalition with the centre-left Labour party (PvdA), which suffered heavy losses in March.

His conciliation efforts fell short during an initial attempt immediately after the vote to form a coalition involving the eco-friendly Green-Left party. Talks collapsed after the parties failed to agree on immigration policy.

Once approved by parliament, the new government’s plans will be finalised and the cabinet appointed – another potentially delicate process that, all being well, should be completed by the week of 23 October.

The Dutch economy, at least, has not suffered from the wait: with Rutte’s previous coalition in charge in a caretaker capacity, GDP has grown by a healthy 3.3% this year and is forecast to grow at a rate of 2.5% in 2018.